Topic 4b

Question 1

trend in melting and boiling point of halogens

Answer 1

increases down the group as the molecules get bigger so there are more and stronger van der waal forces

Question 2

trend in electro negativity of halogens

Answer 2

decreases down the group due to more shielding of the nucleus charge

Question 3

trend in reactivity of the halogens

Answer 3

less reactive down the group due to more shielding and distance from the nucleus so the electron is less likely to be attracted

Question 4

halogen redox reactions

Answer 4

the more reactive halogen replaces the halide ion
if bromide is displaced the mixture will be orange
if iodide is displaced the mixture will be brown

add a organic solvent (hexane)and shake
instead there is orange bromine layer
and purple iodine layer

Question 5

trend in reducing power of halides

Answer 5

increases down the group as the electron is further from the nucleus and there is more shielding

Question 6

test for ammonium compounds

Answer 6

add sodium hydroxide to substance and gently heat

hold red litmus paper and it will go blue